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Too much tofu induces ‘brain aging,'
study shows
By Helen Altonn
Honolulu Star-Bulletin
Tofu is touted for its health benefits, but also may pose health
risks, says a Hawaii scientist.
In comparing the dietary habits and health of the Japanese-American
men in the study group between 1965 and 1993, Dr. Lon White said
the scientists found "a significant link between tofu consumption
during midlife and loss of mental ability and even loss of brain
weight."
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William Harris, M.D. writes: On 11/30/99 I took 16 samples of soy
products for an aluminum assay to University of Hawaii at Manoa
College of Tropical Agriculture and Human Resources. Agricultural
Diagnostic Service Center 1910 East-West Road Sherman 134, Honolulu,
Hawall, 96822.
The results reported on 12/9/99:
The results of this preliminary investigation suggest that the
aluminum concentration in soy products is increased slightly by
cooking, particularly in an aluminum pot, and strongly (as much
as 15-fold) by some methods of tofu production.
Samples 7, 11,13,14, 15, and 16 are produced in Hawaii. I will
not release the manufacturer's names unless requested to do so by
the companies en mass and for the purpose of reviewing their production
methods.
The United States Environmental Protection Agency (EPA), while
apparently having no primary toxicity range for aluminum in food
suggests 0.05 to 0.2 mg/L (.05 to 0.2 ppm) for water in its National
Secondary Drinking Water Regulations:
http://www.epa.gov/OGWDW/wot/appa.html#Inorganic
Table 1
At: http://www.fedreg.com/federalregister/data/12dec/12_10_165.html
There is a listing for Aluminum in water at a pH 6.5-9.0 of 750
mcg/L (.75 mg/L or .75ppm)
The lead author in the as yet unpublished recent study implicating
tofu as a risk factor for Alzheimer's disease in male Japanese living
in Hawaii does not endorse the aluminum-Alzheimer's hypothesis and
suggests that isoflavones in tofu are the etiologic factors.
The published articles
White, L., Petrovitch, H., Ross, G.W., & Masaki K.H. (1996) Association
of mid-life consumption of tofu with late life cognitive impairment
and dementia: The Honolulu-Asia Aging Study. The Neurobiology of
Aging, 17 (suppl 4), S121.
White, L., Petrovich, H., Ross, G. W., Masaki, K. H., Abbot RD,
et al. (1996) Prevalence of dementia in older Japanese-American
men in Hawaii. JAMA, 276, 955-960.
The majority of the Alzheimer's research community also rejects
the aluminum hypothesis, so Dr. White is on fairly solid ground
here. A nice collection of references supporting the tofu-genistein-isoflavone/Alzheimer
hypothesis can be found at:
http://users.erols.com/igoddard/soy.htm
This site also has the Honolulu Star Bulletin report of Dr. White's
Tofu/Alzheimer's study that has not yet been published.
However there are still some lively academic voices suspecting
a role for aluminum in Alzheimer's and other neurodegenerative disease.
A few can be found referenced at:
http://www.bio.unipd.it/~zatta/alumin.htm
http://www.tv.cbc.ca/healthshow/pastitem/adandal.html
http://student.biology.arizona.edu/ad/reference.html
http://student.biology.arizona.edu/ad/allevels.html
The following references can be researched at:
http://www.medportal.com/
Clauberg M., and Joshi, J.G. "Regulation of serine protease activity
by aluminum: Implications for Alzheimer disease." Proceedings of
the National Academy of Sciences of the United States of America.
90 (1993) 1009-12.
Fasman, G D., and Moore, C.D. "The solubilization of model Alzheimer
tangles: Reversing the b-sheet conformation induced by aluminum
with silicates." Proceedings of the National Academy of Sciences
of the United States of America. 91 (1994): 11232- 11235.
Ghany, M.A. et al. "Aluminum-induced Nonenzymatic Phospho-incorporation
into Human Tau and Other Proteins." The Journal of Biological Chemistry.
268 (1993): 11976- 11981.
Hollosi, Miklos et al. "Stable Intrachain and Intrachain complexes
of neurofilament peptides: A putative link between Al and Alzheimer
disease." Proceedings of the National Academy of Sciences of the
United States of America. 91 (1994): 4902-4906.
Jacqmin, Helene et al. "Components of Drinking Water and Risk
of Cogitive Impairment in the Elderly." American Journal of Epidemiology.
139 (1994): 48-57.
Kuroda, Y. et al. "Application of Long-Term Cultured Neurons in
Aging and Neurological Research: Aluminum Neurotoxicity, Synaptic
Degeneration and Alzheimers Disease." Gerontology. 41 (1994): 2-6.
Lovell, M.A. et al. "Laser Microprobe Analysis of Brain Aluminum
in Alzheimers Disease." Annals of Neurology. 33 (1993): 36-42.
Mattson, M.P. "Comparison of the effects of elevated intracellular
aluminum and calcium levels on neuronal survival and tau immunoreactivity."
Brain Research. 602 (1993): 21-31.
McLachlan, D.R. et al. "Desferrioxamine and Alzheimers Disease:
Video Home Behavior Assesment of Clinical Course and Measures of
Brain Aluminum." Therapeutic Drug Monitoring. 15 (1993): 602-607.
McLachlan, D.R. et al. "Risk for neuropathologically confirmed
Alzheimers disease and residual aluminum in municipal drinking water
employing weighted residential histories." Neurology. 46 (1996):
401-405.
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This preliminary aluminum-soy assay needs to be repeated under more
carefully controlled conditions to demonstrate or reject replicability.
Since this one was paid for out of my pocket I leave the remaining
work to interested parties.
-William Harris, M.D.
Honolulu, HI
11/19/99
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